The purpose of the Familial Colon Cancer Clinics and Registry Core is to provide a comprehensive long-term resource for clinical and basic investigation, and at the same time to provide for clinical care of persons and families with inherited risk of colon cancer. The core provides the projects of this program grant the necessary resources for clinical research, for biospecimen collection for genetic and molecular studies, and for computerized data management of both clinical and research materials. Activities of this core will include: mail and telephone subject contact, study registration, administration of informed consent, demographic, epidemiological, medical history and family cancer history data gathering, blood and tissue sampling, and clinical care. Clinical care includes education; genetic counseling and testing; cancer screening; colonoscopy for polyp and cancer diagnosis, treatment and follow-up; upper GI endoscopy as indicated; and appropriate patient referral. Long-term participation is accomplished through the Registry, which provides long-term patient tracking and follow-up reminders, semi-annual patient educational information, and notification of research studies for possible enrollment. The Registry enrolls family members of inherited colon cancer syndromes as well as members with the less well-defined familial colon cancers. Computerized data management deals with medical and family history information, tracking of all patient interactions, genetic and molecular testing information, and blood and tissue sampling, which involves acquisition, processing, storage, tracking and distribution. All data systems and information are secured. The clinics of this core are staffed by investigator physicians, nurses, coordinators, genetic counselors and computer professionals. This core serves as a pivotal resource for program investigations and is a vital point of interaction between research subjects, clinical investigators, basic scientists and information managers. It also allows research to be translational, in that genetic and laboratory findings will be appropriately applied to disease prevention in individuals under study.